Gravity affects light, bending it. Does light affect gravity

In general relativity, the effects of gravitation are ascribed to the curvature of spacetime, instead of being a force. Simplistically, these curvatures cause a free falling object to deviate from its geodesic [which is the notion of a "straight line" to curved spacetime; i.e. the world line of particle free from all external force is a particular type of geodesic]. The situation is analogous to setting a bowling ball on a bed; the heavy ball depresses a nearby region of the bed's surface. If you then roll a marble across this "depression" it feels the curvature created by the massive body. The marble thrown onto the bed moves toward the bowling ball. Because its motion is not along a line and its velocity changes, the marble is now accelerating. Therefore it does not matter whether light has mass in order for it to "bend". Now, onto your question. If you look at gravitation as a result of spacetime curvatures and not a force, you'll realize that light can influence a gravitational field since it possesses momentum and energy [by the equation: E^2 = m^2c^4 + p^2c^2]. They're probably not the only reasons, however.

Edit: I was wrong, which I realized after reading the above posts. Thanks for the question anyway, made me learn a bit.

simply put no. the photon does not have mass, and so cannot affect gravity. The bending is due to the topography of space-time deforming due to the presence of matter, where light travels in a "straight" line in its plane of reference.

well yes.

literally speaking or scientifically speaking yes.

because if gravity has an effect on light. the according to newtons law, light will also have an equal and opposite force acting on gravity

Actually, the answer is yes. In GR, the gravitational field couples to energy density and momentum flow - both of which a photon has.

There haven't yet been any empirical results to know for certain. It is very difficult to measure such a phenomena.

no.